I am working on taking out a loan and the loaners are asking me for an electronically signed copy of 2022's tax return or an 8879 form.

There is no a Form 8879 included in the tax return.  TurboTax is not an ERO.  Your tax return is self-prepared and electronically filed by you.

An e-filed tax return is not physically signed.

Print a copy of the 2022 tax return, sign and date the Form 1040 and give it to the lender. 

Did you efile it?  Did you use the Online version?  

If you efiled, In the PDF of your TurboTax return, the last page of the federal return should be an "electronic postmark" that shows your name, Social Security number, the date and time that you e-filed the return, and the date that the IRS accepted it.